I just bought an i3-8300 with some other parts (see https://pcpartpicker.com/user/adrhc/saved/QqzBbv) and it takes 22.8W/h while idle (and without the Seagate - Barracuda 1 TB). That 22.8W is an average for 5h 50min of light usage (text files edits, short browsing, ~ 10 reboots and console working).
I just bought an i3-8300 with some other parts (see https://pcpartpicker.com/user/adrhc/saved/QqzBbv) and it takes 22.8W/h while idle (and without the Seagate - Barracuda 1 TB). That 22.8W is an average for 5h 50min of light usage (text files edits, short browsing, ~ 10 reboots and console working).